Why are all parts of the cell necessary?

Because one decaing factor of a cell can cause the cell to breakdown and not work.

All living organisms on Earth are divided into cells. The main concept of cell theory is that cells are the basic structural unit for all organisms. Cells are small compartments that hold the biological equipment necessary to keep an organism alive and successful. Living things may be single-celled or they may be very complex such as a human being.

There are smaller pieces that make up cells such as macromolecules and organelles. A protein is an example of a macromolecule while a mitochondrion is an example of an organelle. Cells can also connect to form larger structures. They might group together to form the tissues of the stomach and eventually the entire digestive system. However, in the same way that atoms are the basic unit when you study matter, cells are the basic unit for biology and organisms.

In larger organisms, the main purpose of a cell is to organize. Cells hold a variety of pieces and each cell type has a different purpose. By dividing responsibilities among different groups of cells, it is easier for an organism to survive and grow.

If you were only made of one cell, you would be very limited. You don't find single cells that are as large as a cow. Cells have problems functioning when they get too big. Also, if you were only one cell you couldn't have a nervous system, no muscles for movement, and using the internet would be out of the question. The trillions of cells in your body make your way of life possible.